Service providers typically offer numerous voice and data services to end users of mobile devices. Some examples of voice services are voice calls, call forwarding, call waiting, etc. Some examples of data services are Internet access, streaming audio, streaming video, online gaming, Internet Protocol television (IP-TV), etc.
The first types of wireless or mobile networks that were introduced by services providers were First Generation (1G) and Second Generation (2G) networks. 1G networks provided voice services via analog signals, and then evolved into 2G networks that provided voice services via digital signals. Mobile communications then evolved into 3G (including 2.5G) networks that provided both voice services and data services. For example, 3G networks are able to provide wireless voice telephony, as well as data services such as Internet access, video calls, mobile TV, etc. Some of the 3G networks implemented by service providers were Universal Mobile Telecommunications System (UMTS) networks, Enhanced Voice Data Optimized (EV-DO) networks, General Packet Radio Service (GPRS) networks, etc. Service providers are now beginning to migrate their networks toward Fourth Generation (4G) technologies over Packet-Switched (PS) networks. 4G networks are essentially enhancements to 3G networks in terms of data speeds. For example, a 3G network can provide data speeds of about 3.5 Mbit/sec. According to the International Telecommunication Union (ITU), a 4G network can provide data speeds of 100 Mbit/sec. One example of a 4G network is a Long Term Evolution (LTE) network.
When a mobile device initiates a session over a PS network (e.g., an IP Connectivity Access Network (IP-CAN) session), the session request from the mobile device includes a description of the requested service (e.g., online gaming, IP-TV, etc). The PS network authenticates the mobile device and determines which services the mobile device is authorized to receive. If the requested service is authorized, then the PS network reserves a bearer path (e.g., an IP CAN bearer) of a defined capacity, delay, and bit error rate over a selected Packet Data Network (PDN). A flow of packets may then begin for the service, which is referred to as a data flow or a service data flow over the PDN.
For example, a High Speed Uplink Packet Access/Enhanced Dedicated Channel (HSUPA/EDCH) system achieves high data rates for packet data services by introducing a number of optimizations over the air. One of the key characteristics of HSUPA is the support of flexible bandwidth scheduling. A User Equipment's (UE's) power allocation to transmit data can vary dynamically based on the current channel condition, a Quality of Service (QoS) requirement, and the amount of data that needs to be transmitted. The goal of flexible bandwidth scheduling is to share the uplink power in the most effective way possible. In this regard, an EDCH scheduler is responsible to monitor the communication system load and assign scheduling grant to the different UEs in the system based on an individual UE's need and radio condition and the overall communication system loading. On the other hand, such high flexibility also poses a challenge on radio resource management (RRM), due to the lack of predictability. If the calls are admitted without bound, there will be a point that the EDCH scheduler can not respond effectively such that either the total communication system load will go out of bound or individual UE/UEs will be starved of scheduling grants (thus leading to call drop), or both.
To resolve this issue, there are at least two conventional approaches. First, the communication system can impose a hard limit on the maximum number of EDCH users, beyond which EDCH calls will be rejected. Second, communication system can utilize the actual total communication system load as the criteria for call admission.